The long term clinical objective of this proposal is to obtain biological enhancement of posterolateral spinal arthrodesis using a specific recombinant human growth factor (GF)-treated demineralized bone matrix (DBM). Spinal fusion with autologous bone graft is the gold standard procedure for lumbar fusion, for which bone is usually obtained from iliac crest result in increased morbidity. The aims of this study are to evaluate and compare treatments of DBM alone, GF-treated DBM and "gold standard" autograft alone, in terms of their respective abilities to enhance spinal fusion, potentially negating the need for allograft. This particular GF is known to stimulate proliferation and differentiation of bone cells. Briefly, the proposed study will be performed in skeletally mature coonhounds, which will be followed post-operatively for 16 weeks. Each animal will undergo a surgical procedure intended to produce uninstrumented bilateral posterolateral fusion of the lumbar spine at the L3-L4 and L5-L6 operative levels. The 5 treatment groups will be divided into decortication alone (8 sites), autograft alone (8 sites), DBM alone (8 sites) and GF-treated DBM (2 does, 8 sites each). Individual treatments will be randomized between the operative levels. The fusion maturation between these experimental groups will be assessed surgically, radiographically, biomechanically and histologically. PROPOSED COMMERCIAL APPLICATIONS: Demineralized bone matrix is an ideal carrier for local delivery of growth factors for enhanced osteoinduction. This can be applied to artherodesis, fracture, non-union defects and oral-periodontal defects.